Abstract: The present invention provides methods and compositions for treating subterranean formations whereby the loss of formation absorbable additives from the treating compositions is reduced or prevented.

Abstract: An epoxy resin composition curable to a hard impermeable solid which contains a liquid aromatic diluent having the general formula:C.sub.6 (R.sub.1).sub.6wherein R.sub.1 is hydrogen; a straight or branched chain alkyl radical; a cycloparaffin radical or a mixture thereof; wherein the alkyl and cycloparaffin radicals have within the range of about 1 to 10 carbon atoms; and further wherein at least one R.sub.1 group is said alkyl or cycloparaffin radical.

Abstract: An improved method and composition for consolidating a porous and permeable subterranean particulated formation into a high strength water resistant mass is provided by a particular combination of vinyl monomers, catalyst system and optional features such as solvent, particulate filler, chelates and binders.

Abstract: Apparatus for perforating a well comprised of a closed retrievable carrier formed in an elliptic cylindrical shape and having shaped charge perforating means disposed therein. Upon actuation of the shaped charge perforating means the ellipticity of the carrier is reduced.

Abstract: This invention discloses a method for dissolving a hydrocarbon soluble polymeric internal phase of an aqueous external phase emulsion in a hydrocarbon liquid comprising mixing the emulsion and the hydrocarbon liquid together in the presence of a release agent to thereby cause the polymeric internal phase to dissolve in the hydrocarbon liquid.

Abstract: A method and apparatus for testing and repairing a subsurface conduit using an inflatable packer, wherein the packer includes a fluid filled pressure responsive means, and a fluid pressure conductor means for transmitting fluid pressure to a pressure indicating means located on one end of the packer. The packer is positioned in the conduit such that the fluid filled pressure responsive means is adjacent that portion of the conduit to be tested. The packer is then inflated to isolate the conduit portion to be tested. Air pressure may then be introduced through means in the packer to the isolated conduit portion, and the pressure observed on the pressure indicating means by a television camera located in the subsurface conduit. The packer also includes means for injecting chemical grouting material into a leak in the isolated portion of the conduit.

Abstract: A valve for repetitively allowing and preventing upward fluid flow through a casing string. The valve is convertible from a locked open position permitting reverse upward fluid flow therethrough to a check valve position preventing upward fluid flow therethrough by flowing fluid downwardly through the casing to actuate an indexing J-slot mechanism interconnecting the spring-loaded valve member and the valve body assembly. The valve may be recycled to the locked open position from the check valve position an unlimited number of times through the flowing of fluid in a forward direction downwardly through the casing string.

Abstract: A closure valve for use in oil well testing is presented which provides a full opening flow passage therethrough, and which includes a reverse circulation valve. The closure valve is operated by a power mandrel which is responsive to well annulus pressure, and which is frangibly held in the open position until a predetermined pressure is applied to the fluid in the well annulus. The power mandrel is then frangibly released and moves the closure valve to the closed position. The power mandrel is then disconnected from the closure valve operating mechanism and continues to move to activate a circulation valve opening mechanism. The closure valve includes two normally open ball valves which are spaced apart to trap a sample of formation fluid therebetween when the ball valves are closed.

Abstract: The friction created by rotating and reciprocating a drill pipe in a well penetrating a subterranean formation is reduced by including an ester of an oxazolidine derivative in an aqueous drilling fluid or a mixture of said ester and certain alcohols. This ester of an oxazolidine derivative is represented by the following general formula: ##STR1## wherein n is a whole integer within the range of about 5 to 20.

Abstract: A normally open oil well sampler valve which provides a fully open testing flow path therethrough is presented, wherein the sampler valve is closed under hydraulic control after a predetermined pressure increase in the well annulus pressure. The sampler includes two spaced apart ball valves having a sample chamber therebetween. The operating mechanism moves the ball valves from the open to the closed position simultaneously, and provides a hydraulic lock as well as a mechanical lock to prevent the balls from reopening in the well. The apparatus further includes a circulation valve which is opened after the closing of the sampler valve. One of the ball valves of the apparatus may be selectively removed to provide a single ball, safety closure valve when a well fluid sample is not desired.

Abstract: A composition for inhibiting scale and methods of using said composition consisting of a relatively water-insoluble organic precipitate formed by the reaction of a water-soluble polyelectrolytic organic polymer having an average molecular weight in the range of from about 1,000 to about 100,000 and a water-soluble organic cationic surface active compound.

Abstract: An improved method and apparatus for preventing buildup of cuttings or debris in underwater oil wells. The apparatus includes a drilling tool in the form of a primary tubular member having an internal diameter a predetermined amount greater than the external diameter of a drill string which is run downwardly through a conventional riser pipe string and underwater wellhead assembly. The drilling tool preferably includes an external shoulder formed on the lower end portion thereof for engagement with a corresponding internal shoulder at the juncture of the riser pipe string and the wellhead assembly for supporting the tool independently of the drill string. An annular resilient seal can be included on the lower end portion of the tool for providing a fluid-tight seal between the lower end portion of the tool and the juncture of the riser pipe string and the wellhead assembly. The tool can include a second tubular member connected at its lower end to the lower end of the primary tubular member.

Abstract: A method and apparatus are presented which are particularly useful in testing the production capabilities of offshore oil wells. The apparatus includes a normally closed, weight operated valve which opens a preset delay after the weight operated valve is subjected to sufficient weight such as when a test string is set down upon, and supported by, a packer isolating an underground formation; and a normally open, weight and pressure operated valve which closes immediately when the test string is set down upon the packer. The weight and pressure operated valve expands a sealed chamber when subjected to sufficient weight to close its associated valve. The weight and pressure operated valve also includes a pressure responsive piston which opens and closes the valve, and which is responsive to the pressure in the sealed chamber, and to fluid pressure in the well annulus.

Abstract: This invention relates to methods and additives for scavenging oxygen dissolved and entrained in liquids which are particularly suitable for removing dissolved and entrained oxygen from polymer-containing fluids used in drilling and completing well bores as well as water flood and other procedures carried out in the oil field. The oxygen scavenger additive is sodium dithionite or a mixture thereof with sodium dithionate dispersed in a liquid carrier such as a hydrocarbon.

Abstract: A wellbore circulating valve especially useful in a string of testing tools utilizes a sequentially ratcheted inner mandrel which covers a series of flow ports and is opened by a predetermined sequence of operations which move the mandrel away from the flow ports thereby communicating the annulus with the inner bore of the tool.

Abstract: A method for dissolving clay is disclosed which comprises contacting the clay, in alteration, with separate slugs of a hydrogen ion-containing chemical and a fluoride ion-containing chemical. The hydrogen ions and fluoride ions react on the surface of the clay to produce hydrofluoric acid to dissolve the clay. The method is particularly valuable in dissolving the clay in a mixture of sand and clay without dissolving the sand. This finds immediate value in the practice of acid treating subterranean sandstone formations to increase permeability or to restore permeability damaged by clay.

Abstract: The present invention presents a method and apparatus for stabilizing signals in radioactive well logging tools including providing in the tool a main scintillating crystal and photomultiplier tube for detecting radiation induced in the borehole by a source of radiation, and a reference crystal, including a source of mono-energetic radiation, for producing continuous reference signals of a predetermined energy level. The reference signals are monitored and the spectrum is stabilized to correct for drift of the data signals introduced by the photomultiplier tube and the data transmission system. The preferred mono-energetic reference signals are selected to appear in the energy spectrum at a level which minimizes error. An electronic circuit at the surface provides a correction signal for adjusting the gain of a data signal amplifier responsive to changes in the reference signal, thereby correcting for drift in the data signal.

Abstract: A method and apparatus are presented which are particularly useful in testing the production capabilities of offshore oil wells. The apparatus includes a normally closed, weight operated valve which opens a preset delay after the weight operated valve is subjected to sufficient weight such as when a test string is set down upon, and supported by, a packer isolating an underground formation; and a normally open, weight and pressure operated valve which closes immediately when the test string is set down upon the packer. The weight and pressure operated valve expands a sealed chamber when subjected to sufficient weight to close its associated valve. The weight and pressure operated valve also includes a pressure responsive piston which opens and closes the valve, and which is responsive to the pressure in the sealed chamber, and to fluid pressure in the well annulus.

Abstract: Oil well cementing compositions and processes are produced using a high efficiency sulfoalkylated lignin retarder composition and modifications thereof to produce cement compositions without gelation problems, having high early strength and with precisely controllable setting time.

Abstract: A ball valve type, full opening bore, oil well formation tester utilizes a J-slot mechanism and vertical tool string manipulations to open and close a substantially unrestricted axial bore through the testing tool to allow formation fluid flow through the tool at the command of the tool operator.